@media screen and (min-width: 992px) {
  .box {
    background-color: red;
  }
  li {
    width: 25%;
  }
}
@media screen and (max-width: 991px) and (min-width: 768px) {
  .box {
    background-color: blue;
  }
  li {
    width: 50%;
  }
}
@media screen and (max-width: 767px) {
  .box {
    background-color: pink;
  }
  li {
    width: 100%;
  }
}
